The Field Guide To undersTandinG ‘human error’ It’s in the world’s best interest to read Dekker’s book. The Field Guide is nothing short of a paradigm shift in thinking about ‘human error’, and in my domain of software and Internet engineering, it should be considered required reading. This Third Edition is much better than the Second, and the layout of the material is far more accessible. John allspaw, sVP, infrastructure and operations, etsy If you design equipment or operating procedures, if you investigate accidents or deal with safety, this is an essential book. Sidney Dekker, a leading world authority on ‘human error’ has enhanced his already exceptional “Field Guide” to be a concise, readable guide to both design of equipment and procedures and also the analysis of mishaps. The label ‘human error’ is misleading and its use prevents discovery and correction of the true underlying causes of incidents. So read about hindsight bias, about the difference between the view from inside the system rather than from outside, and about difference between the blunt end (where you should do your work) and the sharp end (where people tend to focus). Read, learn, and put these ideas into practice. The results will be fewer incidents, less damage, less injury. don norman, author of The Design of Everyday Things The Third Edition of Sidney Dekker’s Field Guide to understanding ‘human error’ provides a solid practical framework for anyone wanting to make sense of safety science, human factors analysis, and the New View approach to conducting investigations of incidents and accidents. The trademark direct and passionate style that is common in Dekker’s work focuses on the circumstances of frontline operators and managers working in complex systems, as well as the challenges of the safety investigator. Dekker does not mince his words (“Any human factors investigation that does not take goal conflicts seriously does not take human work seriously”) and is clearly supportive both of sharp end workers, who are tasked with creating safety in the face of resource constraints in complex systems, as well as the investigators, charged with making sense of events that often seem surprising and unpredictable. Several new topics are introduced and enrich the earlier versions of The Field Guide—for instance the chapter on creating a safety department presents important principles for those with the courage to take on such a daunting task. This will be an invaluable resource for any organization serious about understanding and improving the safety of their operations. dr robert robson, Principal advisor, healthcare system safety and accountability, inc. When things go wrong in organisations, one thing is almost always found in the post- mortem: ‘human error’ (in various guises). But one only needs to scratch the surface of system failures to understand that things are not so straightforward. What seems to make sense as a causal catch-all for our everyday slips and blunders snaps when stretched; it fails to explain the context and complexity of our work and systems. There is a better way. In this important book, Sidney Dekker conveys a practical approach for life after ‘human error’. It is both humanistic and systemic; it treats people holistically and non-judgementally, while considering system conditions and dynamics in context. If you are prepared to suspend your own preconceptions and reactions to failure this book will repay you with a practical, highly readable and deeply humane approach to dealing with failure. steven shorrock, european safety Culture Program leader, euroConTrol Comments on the Second edition: Next time I’m lecturing students, I’ll be recommending The Field Guide as required reading! Well done. Barry Kirwan, system safety and human error, eurocontrol, France; Co-editor of Changing Regulation: Controlling Risks in Society and Human Factors Impacts in Air Traffic Management It is accessible, practical, eminently readable and will be of great use to safety practitioners whatever their background. Health & Safety at Work, July 2007 This past year I read your book The Field Guide to understanding human error based on a recommendation of a colleague. I must admit it is one of the best book that I have read on accident prevention and safety. I have been practicing as a construction safety professional for 17 years and have struggled to accurately and completely articulate the concepts you so eloquently describe in your book. Although it draws many examples from an aviation safety standpoint, your book stands up brilliantly as a framework for understanding human error and accident prevention in any industry. Subsequently, I am using it as the text for my course “Safety in the Construction Industry” here at Columbia this fall. The construction industry is so very stuck in the world of the “Old View.” Convincing construction management professional that removing bad apples is not the answer is a tough sell. Your book is making my job quite a bit easier. Thank you. ray master, Columbia university, usa I have every executive in the entire Department of Energy reading The Field Guide as we speak. Todd Conklin, los alamos national laboratory No matter if the reader is an upper level executive in an aerospace company, a member of an accident investigation team, a safety engineer, or a university student, Sidney’s Field Guide is equally as useful. This book presents important ideas for those who regulate human factors investigation and research, making it an essential read for the academician, the research analyst, and the government regulator. International Journal of Applied Aviation Studies, Vol. 7, no. 2 The Field Guide to understanding ‘human error’ Third edition sidney deKKer Griffith University, Australia © sidney dekker 2014 all rights reserved. no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without the prior permission of the publisher. sidney dekker has asserted his right under the Copyright, designs and Patents act, 1988, to be identified as the author of this work. Published by ashgate Publishing limited ashgate Publishing Company Wey Court east 110 Cherry street union road suite 3-1 Farnham Burlington, VT 05401-3818 surrey, Gu9 7PT usa england www.ashgate.com British Library Cataloguing in Publication Data a catalogue record for this book is available from the British library The Library of Congress has cataloged the printed edition as follows: dekker, sidney. The field guide to understanding ‘human error’ / by Sidney Dekker. -- Third edition. pages cm includes bibliographical references and index. isBn 978-1-4724-3904-8 (hardback) -- isBn 978-1-4724-3905-5 (pbk.) -- isBn 978- 1-4724-3907-9 (epub) 1. system failures (engineering) 2. human engineering. 3. industrial accidents. i. Title. Ta169.5.d45 2014 620.8--dc23 2014028900 isBn: 978-1-4724-3904-8 (hBK 978-1-4724-3905-5 (PBK 978-1-4724-3906-2 (eBK) 978-1-4724-3907-9 (ePuB) V Printed in the united Kingdom by henry ling limited, at the dorset Press, dorchester, dT1 1hd Contents List of Figures vii List of Tables xi Acknowledgments xiii Preface xv 1 Two Views of ‘human error’ 1 2 Containing your reactions to Failure 27 3 doing a ‘human error’ investigation 45 4 explaining the Patterns of Breakdown 89 5 understanding your accident model 123 6 Creating an effective safety department 143 7 Building a safety Culture 161 8 abandoning the Fallacy of a Quick Fix 191 Epilogue: Speaking for the Dead 209 Index 213 This page has been left blank intentionally List of Figures Figure 1.1 The “tunnel.” understanding ‘human error’ is about understanding the “inside” perspective—not the outside or hindsight one 8 Figure 2.1 hindsight changes how you look at past decisions. it turns past complexity into a simple, linear story; a binary decision to err or not to err (idea for image by richard Cook) 28 Figure 2.2 different perspectives on a sequence of events: looking from the outside and hindsight you have knowledge of the outcome and risks involved. From the inside, you may have neither 31 Figure. 2.3 Counterfactuals: Going back through a sequence, you wonder why people missed opportunities to direct events away from the eventual outcome. This, however, does not explain their performance 33 Figure. 2.4 The language you use gives away where you stand. here you clearly take the position of retrospective, judgmental outsider 35 Figure 2.5 ‘Judgmental’ means claiming that people should have done something they didn’t, or failed to do something they should have. and then judging them for that. it does not explain their behavior. 36 Figure 2.6 you can try to take the perspective of the people whose assessments and actions you are trying to understand 38 Figure 2.7 Failures can only be understood by looking at the whole system in which they took place. But in our reactions to failure, we often focus on the sharp end, where people were closest to (potentially preventing) the mishap 40 Figure 3.1 Connecting critical process parameters to the sequence of people’s assessments and actions and other junctures 59 Figure 3.2 laying out the various (overlapping) tasks that people were accomplishing during an unfolding situation 60 viii The Field Guide to Understanding ‘Human Error’ Figure 3.3 Micro-matching can mean that you take performance fragments from the stream of events and hold them up against rules or procedures that you deem applicable in hindsight. You don’t explain anything by doing this 63 Figure 3.4 Cherry-picking means taking fragments from all over the record and constructing a story with them that exists only in your hindsight. In reality, those pieces may have had nothing to do with each other 66 Figure 3.5 It is easy to gather cues and indications from a sequence of events and lob them together as in a shopping bag. This is not, however, how people inside the unfolding situation saw those cues presented to them 67 Figure 3.6 See the unfolding world from the point of view of people inside the situation—not from the outside or from hindsight 68 Figure 3.7 The interesting cognitive and coordinative dynamics take place beneath the large psychological label. The label itself explains nothing 69 Figure 3.8 Don’t make a leap of faith, from your facts to a big label that you think explains those facts. Leave an analytic trace that shows how you got to your conclusion 70 Figure 3.9 The way to bridge the gap between facts and conclusions (about those facts) is to find a definition or operationalization in the literature for the phenomenon and start looking in your facts for evidence of it 71 Figure 3.10 Leaving a trace. Using a definition for “loss of effective CRM” that lists misunderstanding the problem, no common goal and uncoordi nated corrective actions, you can find evidence for that in your facts 72 Figure 3.11 Leaving a trace. Overlapping talk, no response when one is expected, unequal turns at talking and offering repair of somebody else’s talk when none is needed together could point to a “loss of effective CRM” 73 Figure 4.1 We make assessments about the world, which update our current understanding. This directs our actions in the world, which change what the world looks like, which in turn updates our understanding, and so forth 90 Figure 4.2 At any one moment, behavior that does not live up to some standard may look like complacency or negligence. But deviance may have become the new norm across an entire operation or organization 112 List of Figures ix Figure 4.3 “Loss of situation awareness” as the difference between what you now know and what other people knew back then 114 Figure 5.1 Laying out a chain of events, including people’s assessments and actions and changes in the process itself 127 Figure 5.2 We may believe that blocking a known pathway to failure somewhere along the way will prevent all similar mishaps 127 Figure 5.3 Without understanding and addressing the deeper and more subtle vulnerabilities that surround failure, we leave opportunities for recurrence open 128 Figure 5.4 The “Swiss Cheese” analogy. Latent and active failures are represented as holes in the layers of defense. These need to line up for an accident to happen (after Reason, 1990) 130 Figure 5.5 Murphy’s law is wrong. What can go wrong usually goes right, and then we draw the wrong conclusion: that it will go right again and again, even if we borrow a little more from our safety margins 137 Figure 5.6 Drift into failure is hard to see inside of the tunnel. Each step away from the norm is only small and offers success on other important measures (for example, time, cost, efficiency, customer satisfaction) 138 Figure 7.1 As the incident rate declines, the fatality rate increases. These data come from a construction industry study on sites between 1977 and 1991.* The horizontal (x) axis shows the fatality rate for all the manhours worked in a given year (represented by the data points in the plot). The vertical (y) axis shows incident frequency for that same year. Efforts to reduce incident rates (which may involve suppressing their reporting) are strongly correlated with a higher fatality rate 177 Figure 7.2 Which safety interventions make sense depends on how safe the system already is (based on René Amalberti’s research).* Over time, our industries have become safer, with many now living at the “thin edge of the wedge.” The safer you become, the more difficult it is to achieve safety improvements 179 Figure 8.1 If you want to understand ‘human error,’ see the unfolding world from the point of view of people inside the situation— not from the outside or from hindsight 194